Research studies have found that postoperative pain ranks as the 2nd most important concern for patients, with about 75% of patients experiencing postoperative pain; and more than 1/3 of orthopedic patients have moderate-to-severe pain on the 1st day after surgery.

Postoperative pain is acute pain that occurs immediately after surgery, including somatic and visceral pain, usually lasting no more than 3~7d , commonly seen in traumatic thoracic surgery and joint replacement and other surgeries that require a longer period of functional exercise. Effective post-surgical analgesia is helpful to reduce patients' pain and promote their recovery.

However, patients and their families always have misconceptions about the use of painkillers, thinking that "painkillers, painkillers are not good for the body, drugs are three times poisonous, but also addictive". No matter how doctors and nurses persuade, patients and their families are "indifferent", preferring to endure, suffering, for example, the night of surgery to ask the patient pain, he said no pain, the next morning, asked him to "rest at night," he said the pain of the night did not sleep, and the prescribed painkillers were not eaten. He did not take the prescribed painkillers. In the end, all kinds of pain lead to physical discomfort, thus affecting the recovery of the disease.